Run perf on Windows

It would be useful to also have the ability to run the perf suite on Windows. One open question would be whether this would run as often as the Linux tests for or if we would kick off Windows tests at a different cadence or on-demand.

This might also help with #181

There's a few different things we'll need to do to fully complete this issue:

• Just get the code building on Windows #865
• Make the collector work in its most basic mode (probably --self-profile) #865
• Use xperf + ETW to capture hardware performance counter metrics like instructions retired. #885
• Coordinate running a Windows box for perf.rlo + set it up
• Add some benchmarks for the Windows box to collect (win-rs or a subset of it might be a good candidate).

Nice to haves:

• https://github.com/rust-lang/rustc-perf/issues/897

Start with the remaining checklist for perf.rlo and the Windows benchmark work. Review how the existing perf suite and win-rs benchmarks are run, then determine the needed Windows machine setup and collection cadence. Done means a Windows box is coordinated for perf.rlo and suitable benchmarks are collecting results.